1. Technical Field of the Invention
This disclosure generally relates to an image forming apparatus, and particularly relates to an image forming apparatus including an ejecting head which ejects a liquid and a maintaining mechanism that maintains the ejecting head.
2. Description of the Related Art
An inkjet recording apparatus is known as a liquid eject recording type image forming apparatus including, for example, an ejecting head which ejects an ink liquid. The liquid eject recording type image forming apparatus may be used as an image forming apparatus of a printing machine, a facsimile machine, a copier, a plotting machine, or a complex machine thereof.
The liquid eject recording type image forming apparatus forms an image on a surface of a paper by ejecting an ink liquid from the ejecting head to the paper. There are two types of liquid eject recording type image forming apparatuses. One is a serial type image forming apparatus which forms an image by scanning an ejecting head in the direction of main scanning direction and by ejecting an ink liquid from the ejecting head. The other is a line type image forming apparatus which includes a line type head and forms an image by ejecting an ink liquid from the line type head without scanning the line type head.
Herein, the terms “image forming” are used to indicate “recording”, “printing a letter, a numeral, or a symbol”, “printing an image”, and/or “printing a document”.
The liquid eject recording type image forming apparatus of the present invention is an image forming device that forms an image by forming an ink liquid on a surface of a paper, a thread, textiles, a fabric, a leather, a metal, a plastic, a glass, a wood, or a ceramic etc. The terms “forming image” are used to indicate not only forming a letter or a figure that have a meaning, but also simply forming an ink liquid on a medium, i.e. forming a pattern etc. that does not have a meaning. The term “ink” is used as an all-inclusive term which means a liquid that can form an image. Thus, the term “ink” may include a recording liquid, a fixing liquid, a liquid body etc. besides so-called ink. Further, the term “sheet” is used as an all-inclusive term which means a medium to be recorded, a recording medium, a recording paper, or a recording paper sheet etc. Thus, the term “sheet” may include not only a paper sheet, but also an OHP sheet, or textiles etc.
The liquid eject recording type image forming apparatus as described above includes the ejecting head which ejects an ink liquid and the maintaining mechanism which maintains the performance of the ejecting head by restoring the ejecting head. The ejecting head includes a nozzle surface from which the ink liquid is ejected, and the maintaining mechanism includes a cap (a cap member) that seals the nozzle surface of the ejecting head. Further, the liquid eject recording type image forming apparatus includes a suctioning function of suctioning an ink liquid in the ejecting head by a suctioning apparatus such as a suction pump which is communicated with the cap of the ejecting head, a wiping function of wiping a surface of the ejecting head by a wiper blade (a wiper member) which is made of an elastic member such as a rubber member, and a pre-ejecting function of ejecting an ink liquid to and around the nozzle in order to remove a thickened ink and a color mixed ink attached thereto. The liquid eject recording type image forming apparatus removes a bubble and a thickened ink in a reservoir, and a particle attached to and around the nozzle, in order to maintain the condition of the ejecting head by using above described functions.
Patent documents 1 and 2 disclose liquid eject recording type image forming apparatuses which include a wiper cleaning member such as a wiper cleaner or a blade cleaner that cleans a wiper member by removing ink attached thereto.    [Patent Document 1] Japanese Patent Laid-Open Publication No. 2003-80720    [Patent Document 2] Japanese Patent Laid-Open Publication No. 09-314852
In a case where a greatly thickened ink is transferred to a wiper cleaning member from a wiper member, the ink remains attached to the wiper cleaning member. It then becomes difficult for the wiper cleaning member to remove the ink from the wiper member when the wiper cleaning member cleans the wiper member. This results in decreasing the wiping performance of the wiper member. Thus, patent document 3 discloses a scraping apparatus that scrapes the ink attached to the wiper cleaning member.    [Patent Document 3] Japanese Patent Laid-Open Publication No. 2005-144912
In a case where an evaporation rate of an ink is high and the ink has a greater tendency to be thickened than a general ink, the ink remains attached to the scraping apparatus and the ink transferred to the scraping apparatus from the wiper cleaning member is deposited onto the scraping apparatus. Thus, the ink attached to the scraping apparatus may contact the ejecting head, and the ejecting head and the sheet may be spotted.